Using Hopg As The Standard Reference Surface For Work Measurements In Air, We Use The Literature Value Of Wf O = 4.475 Ev As The Reference Value (Hansen & Hansen, Reference Hansen And Hansen 2001), In Order To Estimate The Average Dendron Covered Surface Work Function In 4.515 To 4.585 Ev Depending On The Incubation Time.
The work function of solid surfaces can be determined experimentally using absolute or relative approaches. Since hopg usually does not form interface dipoles, even the presence of typical ambient contamination does not change the work function significantly. It should be noted that the difference between the au and al areas must be constant according to the applied direction because there is an absolute difference in work function.
Care Has To Be Taken To Understand Exactly What Is On The Surface And How.
After annealing at 150 °c in ultrahigh vacuum, the work function is. A kpfm image of si will not give you the work function of the material, just as a kpfm image of ti, cr, or al won't give you the work function of those metals either. Work function of eg (red symbols) and qfg (blue symbols) as a function of number of layers.
Figure 2 Shows The Work Function Of Five Samples As A Function Of F G − F 0, Where F G Is The Gate Electric Field Within The Hfo 2 Dielectric Layer, And F
(hopg), which after cleavage has a work function of about 4.6 ev. The work function is also a decisive parameter for the doping level caused by the metal contacts or adsorbates [6, 7] because it determines the relative position of the energy levels of graphene and the dopant. After the h plasma treatment, the nitrogen content decreased.
Here The Use Of Highly Oriented Graphite, Hopg, Is Shown To Work Well As An Additional Standard, Useable In Air Or Vacuum.
The work function measured on au surfaces after I think that i should use hopg as a reference material ( 4.6 ev ) and use kpm to have a value of cpd. The other black symbols represent the position of the dirac point with respect to the fermi level for eg and qfg.
The Work Function W For A Given Surface Is Defined By The Difference =, Where −E Is The Charge Of An Electron, Φ Is The Electrostatic Potential In The Vacuum Nearby The Surface, And E F Is The Fermi Level (Electrochemical Potential Of Electrons) Inside The Material.
For comparison, the work function of highly oriented pyrolytic graphite (hopg) was also measured and it was determined that the work function of mwnt is larger than that of hopg. Therefore, it is useful to have some control over the work function of graphene so that appropriate values can be obtained for specific applications. Also included is the work function of hopg (black diamond).